Propeller



Feb. 6, 1934. J, FQRSHEE 1,945,633

PROPELLER Filed Dec. 26 1931 Eta. 1

i: :11?" 111i. 6 \2 FT I I Z I I l l U INVENTOR.

Joseph M. fianshee ATTORNEY.

Patented Feb. 6, 1934 UNITED STATES PATENT OFFICE Application December 26, 1931 Serial No. 583,198

1 Claim.

My invention relates to improvements in propellers.

The object of my invention is to provide an eflicient propeller when driven at a low rate of speed.

A further object of my invention is to provide a propeller having a flange rearwardly extending and circumferentially positioned on the outer peripheral ends of each blade thereof to resist against slippage while the propeller is in action.

A further object of my invention is to provide a propeller having a short blade with large area by diverging edges from the hub outward.

These and other objects will hereinafter be more fully explained, reference being had to the accompanying drawing forming a part of this specification, and in which like characters will apply to like parts in the different views, and in which:

Fig. l is a diagrammatical lay out of the front of an airplane showing the position of the propellers.

Fig. 2 is a plan view of the rear side of the propeller.

Fig. 3 is a sectional view taken on line 33 in Fig. 2.

Fig. 4 is an end view of the propeller.

My invention herein disclosed consists of a propeller comprising a hub 1 that is drilled axially to receive the outer end of a drive shaft to which it is secured rigidly. The shaft not being shown in Figs. 2 and 4.

oppositely extending from the hub and integrally joined thereto are blades 2 and 2'. The two edges of the blades tangentially intersect the hub and diverge outward therefrom to the extremity of the blade which is segmental with respect to the circumference circumscribed by the outer end of the blade during rotation as a propeller.

Positioned on the outer end of each blade is a flange 3 rearwardly extending at right angles to the body portion of the blades and being integral therewith.

Each blade has a similar twist and being concavo convexo with respect to cross section thereof, but the thickness varies, diverging from the front side A to the rear or opposite side B. The side A converges to an edge as means to cleave its way through the air with least resistance possible, while the side B has a curvature as at C tangentially extending from the convex surface of the body portion of the blade to the concave of the rear surface thereof to form a vacuum during rotation of the propeller.

In Fig. 4 is shown the spiral intersection of the inner ends of the blades to the hub as at D, the wind of which extends from one end of the hub to the other, and being so arranged that the edge portions of each blade aligns on a plane with their respective ends of the hub, and being so positioned the thrust is equalized on the face of the blade from the hub to the flange, and the slippage at the outer end of the blade is retarded thru the medium of the flange.

While I have shown a certain pitch for the blades and varied the thickness thereof from one edge to the other with respect to cross section, I do not wish to be restricted to such alone as the proportion thereof may be changed. It will be further understood that the rotation of said propellers as shown in Fig. 1 will be in opposite directions by reversing the pitch of the blades of one of the propellers, and furthermore, the pairs of propellers may be placed longitudinally along the plane, and such other modifications may be employed as lie within the scope of the appended claim, and having fully described my invention what I claim as new and desire to secure by Letters Patent is:--

In a propeller, a hub, and a pair of blades having a flange on the outer peripheral ends thereof, each blade having a pitch curvature diminishing with respect to the radii of the curve as they approach the hub so that a. portion on the convex side of each blade adjacent the cutting edge of the same for a short distance is void of pitch, then gradually increasing to the rear of the blades, the cutting edge being rounded on the concave side, and the other edge being rounded on the convex side, substantially as shown.

JOSEPH M. FORSHEE. 

